Abrasive articles, such as coated abrasives and bonded abrasives, are used in various industries to machine workpieces, such as by lapping, grinding, or polishing. Machining utilizing abrasive articles spans a wide industrial scope from optics industries, automotive paint repair industries, to metal fabrication industries. In each of these examples, manufacturing facilities use abrasives to remove bulk material or affect surface characteristics of products.
Surface characteristics include shine, texture, and uniformity. For example, manufacturers of metal components use abrasive articles to fine and polish surfaces, and oftentimes desire a uniformly smooth surface. Similarly, optics manufacturers desire abrasive articles that produce defect free surfaces to prevent light diffraction and scattering.
Manufactures also desire abrasive articles that have a high stock removal rate for certain applications. However, there is often a trade-off between removal rate and surface quality. Finer grain abrasive articles typically produce smoother surfaces, yet have lower stock removal rates. Lower stock removal rates lead to slower production and increased cost.
Particularly in the context of coated abrasive articles, manufactures of abrasive articles have introduced surface structures to improve stock removal rate, while maintaining surface quality. Coated abrasive articles having surface structures or patterns of raised abrasive layers, often called engineered or structured abrasives, typically exhibit improved useful life.
However, typical techniques for forming structured abrasive articles are unreliable and suffer from performance limitations. A typical process for forming a structured abrasive article includes coating a backing with a viscous binder, coating the viscous binder with a functional powder, and stamping or rolling structure patterns into the viscous binder. The functional powder prevents the binder from sticking to patterning tools. The binder is subsequently cured.
Imperfect coating of the viscous binder with functional powder leads to binder sticking on patterning tools. Binder sticking produces poor structures, leading to poor product performance and wasted product.
Selection of binders appropriate for typical structured abrasive formation techniques is limited by the process. Typical binders include high loading of traditional fillers that increase the viscosity of the binder. Such traditional fillers affect the mechanical characteristics of the binder. For example, high loading of traditional fillers may adversely affect tensile strength, tensile modulus, and elongation at break characteristics of the binder. Poor mechanical characteristics of the binder allows for loss of abrasive grains, leading to scratching and haze on surfaces and reducing abrasive article life.
Loss of grains also degrades the performance of abrasive articles, leading to frequent replacement. Frequent abrasive article replacement is costly to manufacturers. As such, improved abrasive articles and methods for manufacturing abrasive articles would be desirable.